THAAD Comes to Korea, But at What Cost?

THAAD launch

The recent announcement that South Korea had agreed to deployment of a Terminal High Altitude Area Defense (THAAD) system on its territory marks an important advance in the Obama Administration’s militarized Asia pivot. The THAAD battery threatens to destabilize the military balance of power and draw South Korea into an anti-China alliance with the United States and Japan.

The decision came as the culmination of a long and determined campaign by U.S. political and military leaders to pressure the Park Geun-hye government into sacrificing its national interests and antagonize China, in order to serve U.S. geopolitical goals.

The plan to install a THAAD battery met with strong Chinese and Russian criticism and active resistance by Korean progressive forces and residents of Seongju, where THAAD is to be stationed. U.S. officials claim their intent is purely defensive in nature, to shield South Korea from North Korean ballistic missiles, but there is ample cause for skepticism.

The missiles in a THAAD battery are designed to counter incoming ballistic missiles at an altitude ranging from 40 to 150 kilometers. Given North Korea’s proximity, few, if any, missiles fired by the North would attain such a height, given that the point of a high altitude ballistic missile is to maximize distance. Even so, were the North to fire a high altitude ballistic missile from its farthest point, aimed at the concentration of U.S. forces in Pyeongtaek, it would require nearly three and a half minutes for THAAD to detect and counter-launch. In that period, the incoming missile would have already fallen below an altitude of 40 kilometers, rendering THAAD useless. [1] In a conflict with the South, though, North Korea would rely on its long-range artillery, cruise missiles, and short-range ballistic missiles, flying at an altitude well below THAAD’s range.

The U.S. Department of Defense’s 2014 Assessment of the Ballistic Missile Defense System reports that while all simple non-separating target missiles were successfully intercepted during testing, THAAD had yet to be tested against “more complex” short-range and medium-range ballistic missiles requiring the use of advanced radar algorithms. Furthermore, the test phase found deficiencies in all categories of natural environment testing aside from the wind factor. Nor was testing performed against targets launching electronic countermeasures. [2] In short, although billed as a success, the reality is that the tests failed to replicate real-world scenarios, so claims made about THAAD’s effectiveness are unproven.

So why deploy a THAAD battery in South Korea when it serves no discernible defensive purpose? From the standpoint of U.S. officials, while the missiles are operationally irrelevant, they serve an important practical role in overcoming resistance and persuading a large segment of the Korean population that the battery is necessary for defense.

What truly matters in the THAAD battery destined for Korea is not its weapons, but its AN/TPY-2 X-band radar. Until recently, U.S. officials obfuscated the fact that the radar has two modes of operation: a terminal mode, designed to detect an incoming missile as it approaches its target and trigger the launch of a counter-missile; and a forward-based mode, which can track a missile in its boost phase and pass data back to the U.S.-based anti-missile system. It takes only eight hours to switch the AN/TPY-2 from one mode to the other, [3] and in forward-mode a radar at Seongju would be capable of covering much of eastern China, as well as missiles fired from further afield as they fly within its detection range. [4]

Defense Industry Daily reports that the AN/TPY-2 radar “is always deployed with THAAD, but it can also be used independently as part of any ABM (anti-ballistic missile) infrastructure,” and that flexibility is “carving out an expanding role…that reaches beyond THAAD.” [5]

The wider the range of radar coverage, the more precise the information that is passed to anti-missile batteries stationed in the United States. A THAAD battery is already situated in Guam, and two stand-alone AN/TPY-2 radars are positioned in Japan, where they are integrated into the U.S. missile defense system. [6] No pretense of defense was deemed necessary to win the right-leaning Japanese government’s agreement to allow its territory to be used.

THAAD represents a more indirect approach that was needed to win Korean approval. U.S. military planners could not ignore Korea’s strategic location, and it was inevitable that sooner or later the Park Geun-hye government would succumb to relentless U.S. pressure.

Many Koreans are not so keen to see their nation drawn into an anti-China alliance, particularly at a time when the U.S. seems bent on provocative measures, such as deliberately sailing warships in Chinese territorial waters. Furthermore, many citizens of Seongju are deeply concerned about the health risks of living adjacent to the AN/TPY-2 radar.

There may be a basis for Seongju residents’ worries. Radars transmit pulses of high-frequency electromagnetic fields, and the AN/TPY-2 radar generates radio frequencies in the range of 8.55 to 10 GHz. [7] According to the World Health Organization, radio frequency waves below 10 GHz “penetrate exposed tissues and produce heating due to energy absorption,” and an absorption rate of at least four watts per kilogram “is needed to produce known adverse health effects.” [8]

A counterbalancing factor is that human exposure is sharply reduced outside of the direct path of the primary beam, so where the radar is aimed matters.

The key question for those living in Seongju is the threshold level they will be exposed to. In order to allay concerns, U.S. and South Korean military officials arranged for Korean reporters to visit Guam, which hosts a THAAD battery. There, electromagnetic waves were measured at a distance of 1.6 kilometers from the AN/TPY-2 radar. The population of Seongju is said to live a similar distance from the proposed site of the THAAD battery. Reassuringly, it was reported that the highest measurement taken during the Guam demonstration was 0.0007 watts per square meter, far below any conceivable level of risk. [9] Since electromagnetic waves become weaker with distance, as confirmed by the low reading, the matter of health hazard would seem to have been put to rest.

Or was it? All the Korean reporters were given were readings. Nothing was said about the factors that went into the test. Without that information, the result is meaningless. Was the measurement taken in the line of the main beam, or outside it, where the radiation level would have dropped off dramatically? What was the power setting of the radar during the test? Radars can operate at a variety of power levels. At what angle was the radar? Varying these factors would produce entirely different results, and it is not impossible to imagine that measures were intentionally taken to ensure the lowest possible reading.

The U.S. Army’s field manual for AN/TPY-2 forward-based mode radar operations defines three search plans for the radar while in forward mode. The “standard operations mode,” called Autonomous Search Plans, provides the broadest range and quantity of search sectors. This is the search plan the radar typically uses in forward-based mode, and can be expected to cross a wider area of the immediate vicinity, exposing a broader segment of the population. [10]

The manual cautions that assigned personnel must be vacated from a “keep-out zone” of 100 meters while the radar is operating. A wider range of 3.6 kilometers is defined as a keep-out zone for “uncontrolled personnel,” meaning any unprotected persons. Some Korean commentators have wondered at the apparent discrepancy between the low radiation reading at 1.6 kilometers on Guam and the field manual’s more distant limit for uncontrolled personnel. There is no contradiction, given that the radar in Guam would have been operating in terminal mode during the test, while the Army manual relates to forward-mode. Since forward-mode is intended for detecting launches at long-distance, it would require considerably more power and generate more electromagnetic radiation.

It is possible that long-term exposure to electromagnetic radiation may pose a risk even when the level is low enough to be considered safe. In a paper published in Experimental Oncology, four scientists called for a “re-elaboration of the current safety levels,” based on their studies. The authors conclude, “The carcinogenic effect of MW [microwave radiation] is typically manifested after long-term (up to 10 years and more) exposure.” [11]

It is also possible that there is little or no cause for concern. Whether or not the citizens of Seongju would be exposed to sufficient levels of electromagnetic radiation to induce harmful effects remains an unanswered question. What is certain is that there is no disinterested party with access to the radar and its data to make that determination. The word of U.S. and South Korean officials cannot be trusted, as their focus is on the THAAD’s military utility, to the exclusion of any other concerns. The welfare of the people in Seongju means nothing from that perspective.

Plans call for the radar accompanying the THAAD battery to be initially set to terminal mode. How long and often it remains in that mode is another matter. South Korean Defense Minister Han Min-koo recently reassured the Korean population by asserting, “The government remains committed to not joining the MD [missile defense] shield.” [12] This was the same man, however, who only last year said there was no plan to deploy THAAD on Korean territory, so his credibility is suspect. [13] Not that it matters. The THAAD battery will be operated by U.S. personnel, and South Korea will have no say – or even notification – in how the radar functions.

The price of a THAAD battery amounts to a staggering $1.3 billion, and annual sustainment costs are $22 million. [14] At some point, it is probable that the United States will attempt to offload annual costs onto the Korean people.

As important as health concerns are for those dwelling in Seongju, larger questions face the nation. Should South Korea damage relations with neighboring China, its major trading partner? Do the South Korean people want to see their nation join the U.S. anti-China alliance? Certainly, U. S. officials think it should. Not long after the THAAD announcement, U.S. Ambassador to South Korea Mark Lippert crowed, “We are transforming our alliance. Our two countries are building a new paradigm of cooperation.” [15] And so they are – to Korea’s detriment.

The next Korean presidential election is scheduled for December, 2017. THAAD deployment is slated for earlier in the year, so as to preclude the risk of a new president cancelling the agreement. If opposition by the Korean progressive community and Seongju citizens is determined enough, it could potentially delay deployment past the election and open a space for reversal of this rash decision.


[1] Yoon Min-sik, “THAAD, Capacity and Limitations,” Korea Herald, July 21, 2016

[2] “Until the MDA implements redesigns, the system could experience excessive faults and repairs in inclement weather… The MDA subjected THAAD to natural environments testing, which included temperature extremes, temperature shock, humidity, rain, ice, snow, sand, dust, and wind, and found deficiencies in all areas except wind.”

J. Michael Gilmore, Director, Operational Test and Evaluation, “2014 Assessment of the Ballistic Missile Defense System (BMDS),” U.S. Department of Defense, March 2015.

[3] “Update on TPY-2 X-Band Radars,” Mostly Missile Defense, March 24, 2013.

“Fiscal Year (FY) 2012 Budget Estimates: Procurement, Defense-Wide (section BMDS AN/TPY-2 Radars),” Missile Defense Agency, February 2011.

[4] “In ‘forward-based’ or volume search mode, the TPY-2’s high power output and beam/waveform agility lets it perform air surveillance to very high altitudes at ranges of up to 1,000 km (600 miles).”

“AN/TPY-2: America’s Portable Missile Defense Radar,” Defense Industry Daily, September 14, 2014.

[5] Ibid.

[6] Zach Berger, “Army/Navy Transportable Radar Surveillance (AN/TPY-2),” Missile Defense Advocacy Alliance, February 2016.

“The Sun Never Sets on AN/TPY-2,” Raytheon, September 8, 2014.

[7] “AN/TPY-2 Transportable Radar Surveillance Forward Based X-Band Transportable [FBX-T],”

[8] “Electromagnetic Fields and Public Health: Radars and Human Health,” Fact Sheet N 226, World Health Organization.

[9] Choi Kyong-ae and Defense Ministry Joint Press Corps, “U.S. Reveals Guam THAAD Battery to Calm Radar-Linked Health Woes,” Yonhap, July 18, 2016.

Park Byong-su, “Amid Controversial Deployment, US Shows S. Korean Reporters a THAAD Battery on Guam,” Hankyoreh, July 19, 2016.

[10] ATP 3-27.5: “AN/TYP-2 Forward Based Mode (FBM) Radar Operations,” U.S. Army, April 16, 2012.

[11] I. Yakymenko, E. Sidorik, S. Kyrylenko, V. Chekhun, “Long-Tern Exposure to Microwave Radiation Provokes Cancer Growth: Evidence from Radars and Mobile Communication Systems,” Experimental Oncology, June 2011.

[12] “Local THAAD Will Not Be Incorporated into Wider U.S.-Led MD System: Defense Chief,” Yonhap, July 21, 2016.

[13] Ser Myo-ja, “China’s defense chief raises Thaad,” JoongAng Ilbo, February 5, 2015.

[14] Kang Seung-woo, “Seongju Picked as Site for THAAD Battery,” Korea Times, July 12, 2016.

$200 million annual operation and support cost ( O & S) for nine batteries. The per battery cost, therefore, is estimated at $22 million.

National Research Council of the National Academies, “Making Sense of Ballistic Missile Defense: An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives,” The National Academies Press, 2012.

[15] “U.S., S. Korea Building New Paradigm of Cooperation: Lippert,” Yonhap, July 1,2016.

Originally published at:

THAAD Comes to Korea, But at What Cost?